This invention relates to a sewing seam, particularly for jean fabric.
As is known, in the sewing of seams during the manufacture of such jean or denim clothing apparel as trousers, skirts, jackets, and the like, the fabric edges or flaps to be joined are sewn together using two types of seams which respectively imply the execution of two different sewing methods. A first type of seam is obtained by a sewing method which consists of interlockingly doubling the free edges of the fabric over each other, thus pairing them together to define a seam, then, sewing along the seam using a twin needle sewing machine which produces, from a standard thin yarn, two spaced apart and substantially parallel extending seams with stitches having a relatively small pitch.
Another type of seam implies the execution of a sewing method which consists of pairing together the two fabric flaps as juxtaposed to each other with a first seam, obtained for example by blind stitching at a distance from the free edge of the fabric, followed by a second seam effective to join the free edges together, thereby one portion of each flap will be doubled under the fabric and then secured by sewing on it by means of a twin needle machine to produce a finished seam which is similar to the seam previously described.
The above described seam types, which are adopted universally, while affording generally satisfactory results, have shown to be unable to always provide the required strength of joint at the seam, especially in view of the fact that denim or jean clothing apparel is traditionally intended for "heavy-duty" applications, such as work clothes or sport clothes.
Furthermore, known types of seams for jean fabric which imply the use of a sewing machine which forms relatively closely pitched stitches, may result in some cases in the fabric being weakened by the large number of perforations unavoidably made by the sewing needles.